Hoisting apparatus



' 1939- A. J. CHANTRY HOISTING APPARATUS Filed Oct. 4, 1935 7 Sheets-Sheet 1 w T N A m 0.. md WM IL A ATTORNEY Dec; 19, 1939. A. J. CHANTRY HOISTING APPARATUS Filed 001:. 4, 1935 7 Sheets-Sheet 5 PUMP DRIVEN SUMP INVENTOR 57 6 BY ALLAN JCHAN RY.

WQIM

ATTORNEY Dec. 19, 1939.

Filed Oct 4, 1935 7 Sheets-Sheet 5 VARIABLE SPEED REVERSABLE POWER SOURCE FRICTION FRICTION DRIVE DRIVE I INVENTOR BY ALLAN J. CHANTRY.

ATTORNEY Dec. 19, 1939.

A. J. CHANTRY H OISTING APPARATUS Filed 001:. 4, 1935 7 Sheets-Sheet 6 INVENTOR I ALLAN JCHANTRY.

'Dec. 19, 1939. A. J. CHANTRY 2,133,542

I HOISIING APPARATUS Filed Oct. 4, 1935 7 Sheets-Sheet 7 'ATTORNE I Patented Dec. 19, 1939 UNi'iD STATES PATENT OFF-ICE HOISTING APPARATUS Allan J. Chantry, United States Navy Application October 4, 1935, Serial No, 43,558

.20 Claims. (01. 254-173) (Granted under the act of March 3, 1883, as amended April 30, 19281370 0. G. 757) My present invention relates to an. improved ing description and the accompanying drawings, hoisting apparatus particularly useful in safely illustrating the embodiment of my invention in hoisting an object from a support whichis subthe form of an improved apparatus I have found ject to variable movement in the line of hoist. most satisfactory.

The support may be, and is in the instance illus- Reference is to behad to the accompanying I trated, the ocean whose waves ordinarily make drawings forming a part of this specification in hazardous the hoisting of airplanes or other which like reference characters indicate correvessels or objects therefrom onto either a vessel sponding parts throughout the several views and or a dock. Any other support subject to movein which:

7.0.. ment similar to wave motion, or other variable Fig. 1 illustrates the conventional application movement, is within the scope of the present of my. invention to a vessel whose boom is adapt-, invention, ed to overhang the water, but the samemay be Attempts have heretofore been made to elimias conveniently installed on a dock provided with nate such hazardby providing a hoist driven by a boom likewise overhanging the water, or at any i fiowing oil under pressure, or electric current, other place where the hoisting rope may overin either of opposite directions in order to drive g pp n Object subjectable to like the hoisting mechanism backward to accommoor other objectionable movement; date the recession of the wave, and forward .to Fig. 2 is a a a ma ic View Of one means of accommodate the rising of the wave and .opporvariably applying the requisite friction between tunely manually controlling the continuance of the Source Of P r a d e oist n S-d V- 20 said forward drive to accomplish the hoisting of en thereby;

the object. Fig. 2A is, an enlarged central longitudinal sec- The objects of this invention are to provide tional View of t e eans ed at B an apparatus for facilitating and increasing the Fig. 2B is a similar view of a modification of the :5 safety with which objects may be hoisted from means shown in Fig. 2A comprising the substiwater subject to wave motion, or from a support tution of a variable orifice means in lieu of the liable to similar or other variable or unexpected fixed orifice of Fig. 2A;

movement; to dispense with said driven hoisting 3 is a d a atic View Of a modified mechanism and the complex means required to means of variably applying the requisite friction 30. control the direction and rate of now of their rebetween the source of power and the hoisting quired power; to provide an improved means for means driven thereby;

driving the hoisting mechanism by friction com- Fig. 4 is a top plan view of a plug valve for prising means for varying this friction such that manually controlling the application of the reqthe hoisting cable attachable to the ,object is uisite friction between the source of power and kept free from objectionable slack during the the. hoisting means driven thereby, in the in- 35 non-hoisting period and means for controlling stance shown in Fig. 3; the increase of such friction to effect the hoist- Fig. 5 is a central vertical sectional side elevaing operation; the operation of said apparatus tion view of said valve with its operating handle resulting in the initial automatic maintenance, removed;

after the hoisting cable is attached to the ob- Fig. 6 isasectional view on line 66 of Fig. 5;

ject, of only sufficient idling friction in the drive Fig; '7 is a diagrammatic view of a further modof such hoisting mechanism as will :enable the ified means of variably applying the requisite hoisting cable to move the hoisting mechanism friction between the source of power and the backward against its light friction forward drive, hoisting means driven thereby;

4.5. for instance as the object goes .down, and to Fig. 8 is' a side elevation enlarged view of the 5 enable the idling friction to move the hoisting typical means for controlling the maximum mechanism forward as the object rises, thereby force of said friction applied in each of Figs. 3 keeping the hoisting cable free from objectionand '7 able slack; and to provide a simple, durable,- Fig. 9 is a topplan view of a conventional .30 relatively inexpensive and highly efficient apsource of power and a hoisting means with an 'paratus for this purpose, for use on board ship intermediate friction applying means shown in as well as on land. partial central longitudinal section;

These and other objects of my invention, as Fig. 10 is a diagrammatic elevation view of the well as the details of my improved apparatus, adjacent end of the parts shown in Fig. 9; will be rendered more apparent from the follow- Figs. 11, 11a and 12 are enlarged top plan. views of coacting portions of the friction surfaces optionally employable in the instance shown in Fi 9;

Fig. 13 is a top plan view of the plug valve for manually controlling the application of the requisite friction between the source of power and the hoisting means driven thereby, in the instance shown in Fig. 7;

Fig. 14 is a central vertical sectional side elevation view of the valve shown in Fig. 13 with its operating handle removed;

Fig. 15 is a sectional view on line 15-45 of Fig. 14;

Fig. 16 is a central longitudinal sectional view of the fluid control means diagrammatically indicated at A in Fig. 7 for applying the requisite varying force to the friction drive of the hoisting mechanism;

Fig. 16a is a like view of a modified portion of Fig. 16;

Fig. 1'7 is a sectional view on line l1-Il of Fig. 16;

Fig. 18 is an exterior view of the central portion of the right side of Fig. 17;

Fig. 19 is an enlarged view of one of the centering pistons shown in Fig. 16; and

Fig. 20 is a central sectional side elevation view of certain details of construction of the parts joining the stationary fluid pressure supply pipes to their respective rotary elements comprising the controlled friction application means.

On the ship, or other support In, is mounted a typical boom H having the usual cable and pulley means I 2, I3 for varying the angularity of the boom. Cable [4, having on its outer end a hook or other securing means l5, runs over pulley IS on the outer end of boom H, thence over pulley I1, and thence to the hoisting means IS. The airplane, or other object, 19 adapted to float or rest on the undulatable top of the water, or other suitable variable support, 20, the dotted and full line positions indicating something of the variations in movement of the water or other support 26. However, such variations in movement only comprise a portion of the problem to be solved by my improved method and apparatus installed on a vessel. The other factor thereof is the roll to which the ship is subjected causing the overhanging boom end to be proportionately moved. The wave motion and the ship roll may be out of synchronism, in which case the distance between the object [9 and pulley l6 rapidly vary. In either case the usual hoisting practice subjects objects hoisted to severe jerks liable to injure, more or less seriously, the object or some of its components or content and/ or the hoisting cable or its apparatus or both. My improved apparatus also dispenses with these liabilities.

The hoisting mechanism l8 comprises the typical drum 2!, Figs. 1, 9, a typical manually controlled variable speed power source 22, and a manually controllable variable friction drive means 23, intermediate said elements 2|, 22.

In the instance shown in Figs. 9, 11, and 12, the shaft 24 driven by power source 22 extends through a suitable oil retaining bearing in casing 25 where it is secured concentrically to the head 26 of tube 21. Within tube 21 is a second tube 28 having continuous head 29 at one end provided on its outer surface with a concentric bearing pin 30 seated in bearing 3| upon the inner surface of head 26. The opposite end of tube 28 is provided with head 32 concentrically outward from which extends a tube 33 of reduced diameter provided on its outer end with an antifriction bearing 34, Fig. 20, seated in a recess in bearing projection 25a of the casing 25 through which tube 33 extends. Occupying a recess between the outer end of tube 33 and bearing portion 25a of casing 25 through which said tube extends is a packing gland 35, adjustably secured to the casing at one end while its opposite end is adapted to compress the packing ring which may be inserted in the packing space 36. Preferably concentric with tube 33 and secured to the outer surface of said bearing portion 25a by bolts 31 or otherwise is the flange 38 of a pipe 39, gasket 40 intervening between the juxtaposed surfaces of 25a and 38 to prevent the leakage of the friction control fluid. The bearing 34 is seated between rings 4|, 42 surrounding the tube 33, surplus oil about bearing 34 is confined in bearing 34 by a plate 43 suitably secured over the mouth of the bearing recess in bearing portion 25a in which the bearing 34 is mounted, said plate 43 being provided in its surface contacting with the periphery of tube 33 with a sealing ring 44.

Referring to Fig. 9, secured to the inner surface of tube 2'! by screws 45, or otherwise, are one or more spaced apart pairs of friction rings 46, 41, between which are mounted a pair of pistons 48, 49 whose skirts are telescoped the one over the other, between the juxtaposed telescoping surfaces of which is a sealing ring 56. The opposite outer ends or heads of pistons 48, 49 are adapted to bear against the friction rings 46, 41. The pistons 48, 49 are concentric with and slidable upon the outer surface of tube 28 to which they are keyed or feathered by key-way 5| which drives the pistons revolubly with tube 28. The pistons 48, 49 are provided with bearing flanges respectively 52, 53 of such length that the same leave a space between them when the pistons are telescoped to their minimum extent between the friction rings 46, 41. In this space intermediate said bearing flanges 52, 53 a plurality of holes 54 extend through the wall of tube 28 and on opposite sides of which holes are sealing rings 55 bearing upon the inner surfaces of flanges 52, 53. These sealing rings 50, 55 prevent the escape of pressure fluid through the joints sealed thereby.

Consider that a pressure fluid, preferably oil, be introduced through pipe 39 and tube 33 to the bore of tube 28, and that the structure of the tubes 21,28 and their associated parts are duplicatecl between each pair of friction rings 46, 47, the pressure fluid will flow through openings 54 outwardly between the pistons 48, 49, moving them outwardly and maintainining the bearing surfaces of the heads of said pistons against the friction rings 46, 41 with a force proportionate to the pressure of the fluid, and that power source 22 rotating tube 2'! with its attached friction rings 46, 4'1 will drive attached tubes 28 and 33 with a force proportionate to the friction exerted against rings 46, 4'! by the heads of pistons 48, 49 driving the tube 28.

About the tube 33 intermediate head 32 and the adjacent wall of casing 25 is a head 56 secured to the opposite end of tube 21 and provided with the bearing 51 revolving upon the periphery of the tube 33 for supporting the end of tube 21 opposite its head 26.

The hoisting drum 2| is provided with the shaft 58 revoluble in bearings 59, 60, and GI respectively on portions 62, 63 of base plate 64 and the outer wall of casing 25. Fixed on shaft 58 between bearings 60 and 6| is a gear 64a meshing with an intermediate gear 85, Fig. 10, which in turn meshes with the gear 88 fixed to tube 33 intermediate bearing portion 25a and the adjacent Wall of casing 25.

It will be understood from the foregoing that any rotation of tube 28 imparted by tube 21 and its driving means will correspondingly drive the hoisting drum 2!; andthat when idling friction exists between bearing rings 48, 41 and bearing surfaces of the heads of pistons 48, 49 that the hoisting rope I l attached toan object, for instance I 9, adapted to rise or fall, the hoisting cable will be maintained free from objectionable slack by pulling cable drum 2i backward against the forward drive tendency of tube 2? during the period that the object is descending, and that said idling friction while the object is rising will cause the cable drum 2! to move forward only to the extent necessary to maintain the hoisting cable free from objectionable slack. It will further. be appreciated that when the fluid pressure within tube 28 is increased from the degree necessary for idling friction to that necessary for hoisting the object I9, that the friction of pistons 48, 89 exerted between rings 88, 4! will drive saidhoist- 'ing drum 2I to the extent necessary to complete the hoisting operation.

Whilethe juxtaposed friction surfaces of rings 46, 41 and the heads of pistons 88, 49 may be in a plane, with an opening Mb therebetween for the lubricating disengaging oil pressure, as shown in Fig. 11a, in instances shown in Figs. 11 and 12 these surfaces are irregular and continuous cam surfaces requiring any slippage between such surfaces to telescope the pistons and vary the volume of oil or pressure fluid therebetween.

It will be noted from Fig. 11 that the friction rings 48 are differently constructed from the rings 41. This is due to the fact that the friction rings 88 are the terminal rings having but one friction surface, while the rings 41 have friction surfaces upon opposite sides. In instances shown in Figs. 11 and 12 the pistons 48, 49 are provided respectively with cam projections I8, II spaced apart to conform to the cam cycle of the cam surfaces I2, I3 respectively of friction rings 46, 41, there being spaces 14. or Me, between the portions I8, II, or 41a, 49a, and their coacting cam surfaces.

A pressure fluid, preferably lubricating oil, is maintained from pipe I6 leading into casing 25 and about tube 21 having oil holes 'I'I therein to supply said pressure lubricant to said openings I8.- The last stated pressure is preferably less than the idling friction pressure of the fluid within tube 28 and pistons 48, 49. With such pressure differentials surrounding tube 21 and within tube 28 the pressure surrounding tube 2? may be constantly applied and satisfactorily perform its combined function of lubricating the friction surfaces between rings 45 M and the juxtaposed heads of pistons 48, 49 respectively as well as to release the frictional engagement of such surfaces by forcing the pistons away from contact with such rings when there is within the tube 28 either no pressure or a pressure less than that surrounding tube 21.

In the instance shown in Fig. 11 the friction ring I'I intermediate each pair of pistons 48, 49 is provided on opposite sides with cam surfaces I3 which are staggered relative to each other and with substantial distance between the low and the high points of each of said cam surfaces I3. The several pairs of pistons 48, 48 upon tube 28 are correspondingly staggered so that the cam tom thereof.

projections I8, 'II of one pair of pistons will be, for instance, at the low point of their respective cam surfaces while the next pair of pistons may have their cam portions III, II in engagement with a different portion of their respective'cam surfaces.

In the instance shown in Fig. 12 the cam surfaces of the friction rings are less in height than those indicated in Fig. 11.

This initial understanding of my invention will clarify each of the different applications of the varying friction drives diagrammatically indicated in Figs. 2, 3, and 7.

With reference to Fig. 2, the variable speed electric motor 88, mounted upon a suitable base, drives an oil pump 8|, the electric drive energy for motor 88 coming through wire 82 to a plurality of successive resistance connected contacts 83 to controller contact arm 84 to wire 85, thence through motor 88 to wire 88 completing the circuit. Pump 8| is connected by pipe 98 to cross pipes 9| 91. Pump BI draws its oil through pipe 8? leading from sump 88 whose top is provided with a vent pipe 89 to the atmosphere. Pipe 89, heretofore described as leading to the interior of tube 28, connects with pipe 9I. In pipe 9|, intermediate pipes 39 and 98, is a pressure gauge 92. Pipe 9| crosses but does not connect with pipe I6 which has heretofore been described as leading into the casing 25. Continuing past pipe I6, pipe 9| connects with reducing nipple 93 provided with an orifice 94 leading into pipe 95 which connects with pipe 96 which leads through the top of oil sump 88 and terminates near the bot- Pipe 98 extends beyond pipe 9! and connects with pipe 91 which is adapted to lead pressure 011 first through check valve 539, thence through pressure reducing valve 99, thence to oil pressure gauge I88, thence into and through cross pipe I6, thence through relief valve Iili to pipe 96. The upper end of pipe Iii enters the bottom of tank I82 in which the pressure oil is maintained at a definite level indicated at E88. Tank I82 is provided with a gauge glass I 88 which visually indicates said oil level. From the upper end of tank I82 leads pipe I85 having a stop valve I88. Pipe I85 connects with pipe I81 which leads to a source of air pressure supply I88. Air pressure of, for instance, 25 pounds is adapted to be maintained in the top of tank I82.

In Fig. 2B a valve I99 is substituted in lieu of the pipe reducing nipple 93 having an orifice 94 as described in Fig. 2A. The valve I 89 may be opened to different degrees. This opening of the valve provides an optional variable oil passageway therethrough whereas the area with orifice 94 is fixed.

The operation of the parts shown in Fig. 2 in connection with the heretofore described hoist and its friction drive, is as follows:

When motor 88 is running at a low speed, the flow of oil through the fixed orifice 98 back to sump 88 is such that it maintains a low or idling friction betwen the friction rings 46, ll and their intermediate pistons 48, 89 with the result that undesirable slack is eliminated from the hoisting cable I4 and its attached object I9 may rise and fall at will, as heretofore explained. At the time an object I 9 is to be hoisted, motor 88 is adjusted by control arm 84 to run at hoisting speed, which drives pump 8i faster and thus increases the friction drive between rings 88, 47 and piston heads 88, '49 from an idling friction to a more substantial and hoisting friction drive. The oil pressure gauge 92 indicates the different pressures of the oil during the idling friction as well as during the hoisting friction maintenance. When neither the idling nor the driving pressure is present within tube 28 the pressure of the oil in tank I02, maintained by the air therein enters spaces 14, 14a, and moves the pistons 46, 49 out of engagement with their respective rings 46, 41.

With the fixed orifice 94 the only means of obtaining the substantially different idling and hoisting frictions is by the variation of the speed of motor 80. With the valve I09 substituted for the fixed orifice 94 a second means for obtaining the different idling and hoisting frictions is available. Either of these means may be used alone or in conjunction with each other to obtain said friction drive differences. When the valve I09 is used alone, motor 80 may be run at a constant speed, in which case the degree to which the valve I09 is opened will determine the pressure, or substantially the absence of pressure, prevailing within the tube 28. When valve I09 and variable speed motor 80 are employed together to obtain the required differences in friction drive from an idling to a hoisting degree, motor 80 need not be subjected to as wide a range of speeds as required with fixed orifice 94, and valve I09 need not be subjected to the range of operation necessary where motor 80 is run at a substantially constant speed.

Substituting the structure disclosed in Fig. 3 for that of Fig. 2, the structure and operation are as follows:

The position of the valve IIO as shown in Fig. 3 is in neutral with for instance 25 pounds of oil pressure in tank I28, 150 pounds in tank I2I, and 300 pounds in tank H8, which typical pressure differences remain substantially constant in neutral as well as all other of the operative positions. By neutral position is meant that there is no oil pressure in the friction tension tube 28 and that the same is open to the sump I I9 through opening I20 in the plug valve III] registering with openings I22, I24 in its casing H2.

By turning the plug valve I I9 until its opening III registers with the openings I24a and I24 in its easing II2, oil pressure then flows from the motor driven pump I I3 in order to fill the system, through pipe II4, having open stop valve II5, through check valve IIB to the cross-union with pipe I I1 to tank I I8, filling in the connected pipes until tank II8 is partially full of oil at a predetermined level 219, indicatable by gauge glass I20 on tank H8. At the same time oil is flowing downwardly in pipe 1 i1 through open stop valve I25, thence across, but not connected with, independent pipe 39, thence through reducing valve I26, thence past an opening to pressure gauge I21, thence across, but not connected with, independent pipe I80, thence into pipe 16, thence downwardly into casing 25, which when filled causes the oil to rise into low pressure tank I28, partially filling the same to a predetermined level I29 indicatable through its gauge glass I30. The oil also flows, in filling the system, from pipe II1 to pipe I3! through open stop valve I32, thence past, but not through, independent pipe 39, thence through reducer valve I33, past the opening to pressure gauge I34, thence into its branch pipe I35 leading into the bottom of the medium pressure tank I2I, thence filling the same to a predetermined level I36, indicatable upon itsgauge glass I31. In order to complete the filling of the system, compressed air from a source of air pressure I38 is led through pipe I39 thence through pipe I40, having open stop valve MI, in-

to the top of tank I I8 until an air pressure of for instance, 300 pounds is maintained therein above the oil level II9, whereupon the valve I4I may be closed, or left open if the pressure in source I38 is maintained at the pressure within tank II8. This air pressure flows also through relief valve I42, thence through open stop valve I43, thence across, but not through, independent pipe 39 and through reducer. valve I44 to branch pipe I45, having open stop valve I46 into the top of tank I2I until it builds up an air pressure above the oil level I36 therein to, for instance, 150 pounds per square inch, thence through relief valve I41 across, but not through independent pipe I3I, thence through reducer valve I49 to branch pipe I50, having stop valve I5I and entering the top of tank I28. Beyond branch pipe I58, pipe I39 is provided with a relief valve I52, which may relieve to the atmosphere. In case the source I38 of air pressure contain air substantially in excess of the maximum pressure in tank II8 the pipe I39 must be provided, between said source and branch pipe I40, with a reducer valve I53; but where source I38 contains merely the requisite air pressure for tank II8 the reducer valve I53 may be dispensed with. In order to fill the remainder of the system, including pipe 39, which is done before the air pressure is placed upon the tanks I28, I2I and H8, the stem IIOa of the plug valve is turned until its opening I I I registers with openings I24a and I24 in its casing I I2, in which position oil from pipe I I1 enters branch pipe I60 leading across, but not connecting with pipe I80, to said opening I24a so that the oil therein flows through openings I24a, III and I24 into pipe 39 until it fills the tension space within tube 28 in casing 25.

In filling the system the motor driven pump II3 takes its oil supply by way of pipe I6I from sump II9 having a vent IE2 to the atmosphere, and into which sump through pipe I80 the surplus oil flows from the system.

The sump connecting pipe I80 leads to opening I22 in valve casing I I2 of valve I I0. The pipe I3I, receiving pressure oil from pipe H4 and H1, leads past its branch pipe I35 to opening I220 in casing II2 (opposite opening I22) of valve IIO.

At a point between branch pipe I35 and valve III), pipe I3I is provided with a branch pipe I63,

having relief valve I64, connecting with said pipe Preferably in pipe II4 between its check valve H6 and its connection with pipe H1 is a branch pipe I65 leading the pressure oil to I66 which diagrammatically indicates, as conventionally shown in Fig. 8, a metallic diaphragm I61 receiving the pressure oil from pipe I65, insulation strips I68 secured on opposite sides thereof and insulation block I69 secured at the center of the head of the diaphragm I61. To the insulation element I68 is attached a metallic bar I10 to which is hinged a metallic bar or switch tongue I1I whose unpivoted end is normally held by spring I13 in contact with contact plate I12 secured on insulation I68, said switch tongue I1I extending across block I69 so that when the oil pressure swells diaphragm to the desired maximum the block I69 will break the electric circuit through wires I14, I15 through tongue I1I from the source of electric energy to the electric motor element of motor driven pump I I3, thus stopping the pump and precluding a pressure higher than said maximum.

In Figures 3 and 4, the plug valve assembly I I0 is set in neutral position, in which the curved opening I20 then connects said opening I22 (terminal of pipe I88) with said opening I24 (terminal of pipe 39), thus draining the surplus oil within tube 28, Fig. 9, through piping I80 to the sump II9.

When plug I I911 of valve assembly I I is turned to the tension position its opening I20 registers with said. openings I22 and I24a in which position the tension pressure maintained on the oil in tank I2I causes the oil therein to flow through piping I35, I3I, openings I22a, I20, I24 to pipe 39 into tube 28, Fig. 9, thence through openings 54 where it exerts this requisite tension pressure within and between pistons 48, 49 causing the heads of said pistons to exert the required tension friction against their juxtaposed surfaces of friction rings 46, 41 respectively. This keeps objectionable slack out of hoisting cable I4, Fig. 1, by said cable moving hoisting drum 2I and its drivingly attached tube 28, and its pairs of pistons 48, 49 slidingly keyed to tube 28, backward against the drive (of variable power source 22, through shaft 24, tube 21 and friction rings 46, 41 in light frictional engagement with the heads of said pistons) when object I9 goes down relative to pulley IS on the end of boom I I, Fig. 1, and said slack is also kept out of cable I4 by said light friction drive causing the hoisting means to be driven forward by said light or tension friction when the support 20 of object I9 rises relative to said pulley I6.

Should for any reason a tension, less than that normally maintainable by the pressure within tank I2 I, be desired in the degre of the frictional engagement between rings 48, 4'! and pistons 48, 49 normally maintained by the valve IIlIa when its opening I28 connects openings I 22a and I24, said valve may be rocked back and forth between its neutral and tension positions.

To attain the requisite hoisting friction between rings 48, 41 and pistons 48, 4-9, the plug valve I I911 is turned to the maximum tension position, in which openings I 20, I22 and I241; are connected, to the hoisting position indicated in Fig. 4', in which opening I I i in I la registers with openings I24, 124a. and the terminals of opening I20 are on opposite sides of opening I22a. In said hoisting position oil from pump H9 flows through piping H4, H1, I69 and/or tank H8 and piping IITI. I89, through openings I241, III, I24 and pipe 39 to tube 28, at the pressure maintained in tank H8, where it increases the idling or tension friction to the required hoisting friction. By varying the speed of power source 22, by control means 220. diagrammatically shown in the hoisting operation may be performed at the desired rate, and the valve assembly III] and the speed and direction control means 22a of power source I 22 are preferably conveniently juxtaposed for their convenient operation by one person.

The stem IIIib of plug II 9a of valve assembly I!!! is provided with operating handle IIEIc having a pointer IIIicZ indicating the several neu tral, tension and hoist positions designated upon the exposed portion of valve assembly I Iii which is provided with lugs IIlle between which handle Mile may only move between the said neutral and hoist limits of movement.

When the hoisting operation is completed by the deposit of object I9 upon ship Ill, or other desired support, the plug valve II Oct is moved first to the tension position, Fig. l, and thence to neutral when cable I4 is desired to be detached.

In the'species of apparatus disclosed in Figs. 3, l, 5, 6, the plug valve IIIia was subjected to the pressure of the oil in pipes I3I, I89 and was therefore not readily movable. This is overcome in the species disclosed in Fig. 7, by the provision of a master control diagrammatically indicated at A in Fig. 7, and in detail in Figs. 16, 17, 18, for the control of the presence or absence of the tension and the hoisting oil pressures within the pair of tubes 28, Fig. 9 and the pilot valve assembly I90 shown diagrammatically in duplicatefin Fig. '7 (the duplicates being located at different places one of which may be more convenient than the other for difierent hoisting operations or portions thereof) and in detail in Figs. 13, 14, 15.

In connection with the species of apparatus disclosed in Fig. '7, a second pair of tubes 21, 28

and their associated mechanism is mounted within casing 25, the second tube 21 having gear I82 fixed on its shaft 2 2 and meshing with gear I33 fixed on shaft 24 of the first tube 21, while the second tube 28 has fixed to its tube 33 a gear I84 meshing with gear I85 conveniently fixed on shaft 58 of hoisting drum 2I. The friction or cam surface or surfaces of rings 46a, 41a and pistons 48a, 99a, (instead of their friction or cam surfaces being formed exactly like those of rings 46, 4'5

of the first described tubes 22, 28 shown at theright portion of Fig. 9 and in Fig. 11) may be formed of plane surfaces, with one or more openings 'l Ia therebetween, as indicated in Fig. 11a, but preferably the same are formed as shown in Fig. 12 in which the undulations in the cam surface of ring 4211 (and those of corresponding ring 46a) are less in degree thanshown in Fig. 11 for the corresponding rings 46, 41.

In Fig. 7 the constant speed motor pump IQI draws its oil supply through pipe I92 from sump I93 having vent I94 to the atmosphere, and supplies the same under, for instance substantially ing into the bottom of tank I91 until the oil I therein is at, for instance, said 300 pounds pressure and a definite level I98 indicated upon gauge glass I99 with which said tank is provided. Connecting with pipe IBM is a branch pipe 282, having pressure gauge 2% and open stop valve 222 and branch pipes 203 leading to the upper quarter of each of the plug valve assemblies I99.

Pipe I9'Ia is also provided with a branch pipe 204, provided with stop valve 225, reducing valve 286 and pressure gauge 20?, and connects with pipe I8 which crosses, but does not connect with pipe I95, anddoes connect the interior of casing with the bottom of the friction relief pressure tank 228, in which and in said casing 25, pipes 25 and 224 oil pressure is maintained at, for instance, 25 pounds per square inch, at a level of 299 indicated by gauge glass 2H1 on said tank 298, by said reducing valve 286, and which pressure is indicated by gauge 2131.

Pipe 76 is provided with a branch pipe 2 I I having relief valve 2H5, connecting with pipe 2I2 leading into and terminating preferably near the bottom of sump tank I93. Pipe I95 extends preferably past pipe I921; and is provided with a pressure gauge 2I3, relief valve 2M and leads'into sump pipe 2 I2 which rises above branch pipe 2! I and is connected by branch pipes 2 i 5 to the lower quarter of each of valve assemblies I99.

From pipe I9'Ia branch pipes 2 II, 2 it lead therefrom each past, but not connected with, pipe I95 to near the opposite interiors of tube 2 l 9, Figs. '7, 16, having closed or closable opposite ends 229. Slidably mounted in the bore of tube H9,

and between pipes 2I'I, 2I8, are pistons 22!, 222

substantially separated from each other by piston rod 223 rigidly secured to and extending between said pistons. At a point intermediate pistons 22I, 222 said rod 223, in the instance shown in Figs. 16, 17, is bifurcated and providedwith a pin 224 into which bifurcation and over which pin 224 fits the bifurcated end of lever 225 fulcrumed, in the instance shown, intermediate its ends on pin 226 rigid with or secured to said lever, said pin 226 being provided with bearings in the walls of housing 221 connecting tube 2I9 with a tube 228 and covering and connecting openings 229, 230 through the walls of said tubes respectively and through which openings the opposite ends of said lever 225 extend. From the bore of tube Eli? and adjacent the inner faces of pistons 22I, 222 lead pipes 23I, 232 respectively to the inlet of the first and second tubes 28, and each of which last stated pipes perform the function heretofore stated of pipe 39 heretofore described in connection with Figs. 2 and 3. At a point intermediate pipes 23I, 232 and from the bore of tube 2I9 leads a pipe 233, as indicated in Fig. '7, across, but uncommunicating with, each of pipes 23I and 16, thence said pipe leads into pipe 2I2.

Within said tube 228, on opposite sides of its opening 230, are reciprocatable pistons 234, 235 rigidly secured near opposite ends of piston rod 236. The opposite ends of tube 223 are provided with removable heads 231 through which respectively pass pipes 238, 239. In the instance shown in Fig. 7, the pipe 230 crosses over, but is not in communication with, each of pipes 2I8, I95, to branch pipes 240 leading to the right quarter of each of the plug valve assemblies I90, and both branch pipes 240 pass over, but are not in communication with, sump return pipe 2I2. In like instance, said pipe 239 extends across, but is not in communication with, pipe I95, and terminates in two branch pipes 24 I, to the left quarter of each plug valve assembly I90, the left of which branch 24I crosses over, but is out of communication with pipe 200, and the right of which branch 24I crosses over, but is out of communication with, each of pipes 200, 230, the right branch of 240, and pipe 2I2.

From a source of air pressure supply 250 extends air supply pipe 25I across, but not communicating with, the left branch of pipe 24I, the pipe 200, and having reducer valve 252, pressure gauge 253 and branch pipe 254 leading air through openable stop valve 255 through the top of tank I91 while in said valve 252 is adapted to maintain a pressure of air of, for instance 300 pounds per square inch against the top I08 of the oil therein. Pipe 25I extends past branch pipe 254, through openable stop valve 256, thence across, but not communicating with, pipe 238, the right branch of pipe 240, to reducer valve 251, and pressure gauge 258 to relief valve 259 to the atmosphere, and preferably between valves 251, 259, from pipe 25I leads a branch pipe 200 into the top of tank 208 wherein said valves 251, 259 maintain a definite air pressure of, for instance, 25 pounds per square inch against the top 209 of the oil therein.

From the oil pressure assembly I66, heretofore described in connection with Figs. 3 and 8, oil supply pipe I65 leads into said pipe I95 past check valve I96.

Each of the plug valve assemblies comprises in the instance shown a tapering plug valve 210, Figs. '7, 14., 15, mounted in casing 2', cover 212 suitably secured thereto and through which stem 213 of valve 210 extends surrounded by a conventional packing assembly I14 preventing leakage about stem 213.

Substantially the same handle IIOc with indicator H011 and lugs IIOe employed in Fig. 4 with valve assembly H0 are employed in Fig. 13 with valve assembly I90.

Extending laterally through the plug valve 210 ina common plane are separated elbow openings 215, 216, Figs. '7, 15, whose termini are located at substantially 90 apart relative to their own ends as well as between the termini of said different elbow openings. In the same plane with but intermediate said termini are the terminals 211 of a three way opening 218 whose intermediate portion, in the instance shown, dips below the elbow openings 215, 216, Fig. 14 to conveniently and inexpensively attain a path independent of openings 215, 216.

In the diagrammatic view of said assembly I90, Fig. 7, the three way opening 218 and its said terminals 211 are shown in light full lines, while the elbow openings 215, 216 are shown in light dotted lines, each in their neutra position, and the elbow openings are there shown in their respective other positions by heavy dotted lines.

But one of the valve assemblies I 90 is usable in any one tensiom'ng and hoisting operation, and the one so used is returned to neutral position so that either assembly I90 may be efiiciently subsequently employed.

In the neutral position of the elements A and C, shown in Fig. 7, the pipes 238, 239, 2I5, 2I2 are connected to sump I93 by the three way opening 211-218 of valve assembly I90. In this position there is an equalization of substantially zero pressure on the outer surfaces of pistons 234, 235 in tube 228 of assembly A.

When handle IIOc of, for instance, the left valve assembly I90 is moved to tension position, the elbow opening 215 connects the left pipe 203 and pipe 200 with, for instance, the left branch pipe 240 and pipe 238, and elbow opening 216 connects pipe 2I52I2 and sump I93 with left branch of pipe 24I and pipe 239, while the three way opening 211-218 occupies a blanked intermediate position. In such position the pressure oil flows from tank I91 to pipes I91a, 200, 203 (and/or from pump I9I through pipes I95, I91a, 200, 203) thence through registering elbow opening 215 to pipe 240-238 and exerts its pressure against and moves piston 234 to the left in tube 228. This movement likewise moves piston rod 236 and its attached piston 235, and, through lever 225 piston rod 223 and its attached pistons 22I, 222 with piston 222, from the neutral" position shown in full lines more clearly in Fig. 16 to the dotted position of pistons 22I, 222 shown respectively at 22Ia, 222a. This latter movement disconnects pipe 232 from connection with the sump I 93 through pipes 233 and 2 I2, and leaves pipe 23I- connected to sump I93 through pipes 233 and 2I2, and admits the oil pressure in tank I91 through pipes 191a, 2", (and/or the oil pressure from pump I9I through pipes I95, I91a, 2 I1) to the left end of tube 2I9 and thence through pipe 232 into tube 28a and through openings 54a to exert its pressure between the pairs of pistons 48a. 49a and produces the requisite idling friction between the outer surfaces of said pistons and the juxtaposed surfaces of rings a, 41a shown in Fig. 12 or optionally of the rings 46b, 41b indicated in Fig. 11a. This idling friction functions as heretofore indicated generally as well as in connection with Figs. 2 and 3.

In the species of my invention illustrated typically in Fig. 7 the same oil pressure within tank 191, and/or that provided by pump 191, produces the idling as well as the hoisting friction. However, in any adaptation of said species of my invention wherein the pressure of the oil thus supplied to affect the idling friction is desired to be less than such pressure affecting the hoisting friction, such lesser pressure may be conveniently achieved, for instance, by the following adaptation of the pressure relief opening 94 employed in Figs. 2 and'2A:

In the instance shown in Fig. 16a, only atthe tension position of piston 222, indicated in dotted lines in Fig. '16 and in full lines in Fig. 16a,'the bore of tube 219 is provided with a depression of the desired area extending around the piston 222 in said position and which depression forms an orifice 94a functioning only in said "tension position of piston 222 to bypass some of tension oil' past piston 222 and into the sump connecting pipe 233. In said instance, the tension oil, which comes only through pipe 211 to the left end of tube 219, thence part of the tension oil passes into tube 222 and thence into tension tube 28a, while the other part of the tension oil bypasses around piston 222, only when in its tension position 222a, and into the sump 193 through pipe 233. The area of said orifice 94a is such as to affect the desired reduction of the oil pressure affecting the tension or idling friction.

In all the other positions of piston 222 said orifice 94a becomes only a localized increment in the area of tube 219.

When the hoisting operation is desired in the instance of the structure disclosed in Fig. 7, the operating handle 1190 of valve assembly 190, Figs. 13,7, is moved from the last stated tension position rapidly to the hoist position. In this position the elbow openings 275, 2'16 of plug valve 2m register respectively with pipes 240, 215 and 293, 2 11. Such position connects pipe 238 and the, for instance, left branch of pipe 249 through elhow opening 2'15 to, in said instance, the left branch of pipe 215, and pipe 212 to sump 193 so that oil in the right end of tube 228 may be displaced therefrom and drained into the sump 193. This hoist position, in said instance, enables the pressure oil in tank 19? to flow through pipes lil'la, (and/or from pump 191 through pipe 195 and the intermediate portion of pipe 191a), thence through pipe 229, the left branch pipe 283. thence through elbow opening 2'16 to and. through the left branch of pipe 241 to and through pipe 232 into the left end of tube 228 where it exerts its pressure against piston 235. moves pistons 234, 235, with their rod 236, to the right, and through lever 225 also moves piston rod 223 and its pistons 221, 222 to the left to the dotted positions respectively shown at 221b, 2222), in Fig. 1.6. In the last stated positions the oil pressure from tank 19'! flows through pipes 191a and 213 (and/or from pump 191 through pipes 195, liila and 218) into the right end of tube 219 and thence into pipe 221 and tube 28 of Fig. 9, thence through openings 54 into the space between the pairs of pistons 48, 49where it causes the outer surfaces of said pistons to engage, with the force requisite to affect the hoisting operation, the juxtaposed surfaces of rings 16, 4'1, fixed to tube 21, driven by the power source 22, which source may be driven at the requisite speed by the manual manipulation of the appropriate one of a pair of control assemblies 22a, Fig. 9, each Such pressure of which is located adjacent its respective one of the duplicate control valve assemblies 191 diagrammatically indicated in Fig. 7.

When the hoisting operation is completed by the deposit of the hoisted object 19 upon the vesby the oil pressure valve 206, flows, to supply any slight leakage loss in casing 25, from tank 208, through pipe 12 (and/or from tank 191 to pipe 191a, and/or from pump 191 through pipes 195 and 191a), thencethrough pipe 204 and its then open stop valve 295 and its reducer valve 2116 to pipe '16, thence through the remainder of pipe 1.6

to within the casing 25, thence through openings '11, Tia, to the spaces 14, 74a, respectively of tubes 28, 23a, if the instance shown in Figs. 11, 12, or into space Nb of the instance shown in Fig. 11a. In said spaces '14, 14a, or Mb, said pressure oil accomplishes the efficient lubrication of the juxtaposed surfaces of the rings and their coacting pistons, as well as to affect the disengagement of said juxtaposed surfaces. 'In the tension position the oil pressure in the space '14 of the hoisting tension tube 28 (the higher hoisting pressure of the oil being then absent from tube 28) accomplishes the same lubricating and disengagement functions- In the hoist position, the hoisting pressure of the oil being then within tube 28, and which pressure is substantially in excess of the'lubricating and disengaging pressure of the oil within casing and about tubes 28, 29a and in the spaces M, 1 1 a or 54b, the oil in said spaces is displaced from said spaces to the extent necessary to attain the requisite hoisting engagement of the juxtaposed surfaces of the hoisting rings and pistons. The oil confined by casing 25 and between these juxtaposed tension and hoisting surfaces will, by any slippage of said surfaces, be caused to pulsate as such spaces are thereby'varied in volume, and the pulsating oil may correspondingly pulsate through openings 54, 54a and pipe 16 and its connections. Such slippage of said juxtaposed tension, or idling friction, surfaces keeps'the hoisting cable Hi free from objectionable slack as heretofore explained. Such slippage of the juxtaposed surfaces affecting the hoisting tension is designed to prevent the liability of the breakage of the hoisting cable and/or the stalling of the source of hoisting power 22 at its then speed, and in the latter case said slippage affords indication of the necessity of, for instance, an increase in the speed of source 22 by means of the convenient one of the control assemblies 22a.

In the instance disclosed in Figs. 11, 12, slippage of the pistons upon their cooperating rings involves as factors the extent of the pressure of the oil, within the pistons exerted upon the rings, and displacements, through openings 54, of some of such oil from Within the pistons. Such displacements also occasion corresponding pulsations of the pressure oil within the affected tube 28 or 28a, and the oil connections therewith.

The shaft 228, forming the fulcrum of and secured to lever 225, projects through one wall of the housing 22?, and on said projection is secured indicating hand 225a, Figs. 1'7, 18, adapted to indicate the appropriate one of the positions 221a designated in Fig. 18 as hoist, neutral and tension.

In order to center the pistons 234, 235, their rod 236, lever 225 and indicating hand 226a at neutral position, in the instance shown in Fig. 16, the opposite ends of tube 228 are provided with an enlarged bore 302 leaving a shoulder 303, and each enlarged bore of tube 228 is provided with a preferably free piston 300, having a skirt Sill slidable within its appropriate enlarged bore. Each piston 300 is adapted, at neutral position 221a, to rest against its said shoulder 302 and against the adjacent end of piston rod 23%. Within the skirt 30I and extending through the head of each piston 300 are a plurality of oil ports 304, Fig. 19, preferably surrounding a central boss 305 which thickens said head at the point of contact with the end of piston rod 236, whose length is such as to afford such contact at opposite ends when pistons 300 bear against their respective shoulders 303. Within the skirt 30I of each piston 300 is an end of a coil spring 300, Fig. 16, whose outer ends abut against their respective adjacent surface of heads 237 of the 25 opposite ends of tube 228. To retain and center the outer end of each spring 303 is a cone 301 secured to and projecting within spring 306 from each head 231. In the instance shown in Fig. 16, wherein the obvious difiiculties of an off center inlet of the pipes 238, 239 through their respective heads 237 are avoided, said cones 30'! are formed hollow, to receive the pressure oil from their respective pipes 238, 230 and communicate the same to tube 228 through the open apex of cones 30'! and ports 30% through pistons 300. The function of pistons 300 and their springs 30'! is to center piston rod 236 and its connected parts, heretofore described, at neutral position shown by the full line position of the movable parts of Fig. 16 and in Fig. 18.

The rapidity with which either valve assembly I90, Figs. '7, 13, 14, 15, is most advantageously operable would be impeded should it be required to directly affect the flow of the pressure oil respectively into pipes 23 I, 232. Such impedance is overcome by having either valve assembly I90 control merely the flow of pressure oil into one or the other end of tube 228, Fig. 16 where the force of such oil operates connected pistons 234, 235, which correspondingly operate pistons 22I, 222 in tube 233 to appropriately control the flow of the pressure oil into either of pipes 23!, 232. However, where such impedance is unobjectionable the valve assembly I90, or its mechanical equivalent, may directly control the flow of oil to and from pipes 23I, 232, in which case the means disclosed in Figs. 16, 1'7, 18 may be dispensed with and pipe 231, instead of leading into one end of tube 228, will be connected to pipe 23I, while pipe 239, instead of leading into its end of tube 228, will be connected to pipe 232, as those skilled in the art will appreciate from the drawings and the preceding description thereof.

Various modifications and changes may be made in the application and practice of my invention without departing from its essence and without exceeding the due scope of the appended claims.

The invention herein described may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

Having now so fully described my invention 75 that others skilled in the art may therefrom make and use the same, what I claim and desire to secure by Letters Patent is:

1. In a hoisting apparatus, the combination of hoisting means including an element adapted to be connected to the object to be hoisted, said object being liable to impairment due to shock incident to sudden motion, the support of said object being subject to sudden variable movement coincident with the direction of hoist, a source of power, means having juxtaposed friction surfaces for drivingly connecting the hoisting means and said source of power, means for applying power from said source to the friction surfaces in the direction of hoist, means for contacting said friction surfaces with forces of different magnitude. one of which forces when applied to said friction surfaces being sufficient only to maintain the element of the hoisting means free from objectionable slack while admitting of movement of said element by a part of the force of gravity of the object in an opposite direction and against the force of said applied power to compensate for such movement of the support, the second of said forces contacting said friction surfaces being of such magnitude as to afford sufficient friction to hoist the object, and means for increasing the magnitude of saidv power for hoisting the object.

2. In a hoisting apparatus, the combination of hoisting means including an element adapted to be connected to the object to be hoisted, which is liable to impairment due to shock incident to sudden motion, the support of said object being subject to sudden variable movement coincident with the direction of hoist, power means adapted to move the hoisting means only in the direction of hoist, friction clutch means having juxtaposed friction surfaces provided with lubricating spaces at intervals between and connecting the power means to the hoisting means, and means for engaging the friction members of the friction clutch means with forces of different magnitude, one of which forces being sufiicient to hoist the object and the other force being sufiicient only to maintain the element of the hoisting means free from objectionable slack while admitting of movement of said element against the direction thereon of the power means and in a direction opposite to the direction of hoist by only a portion of the force of gravity of the object when exerted upon said element by such motion of the object in a direction opposite to the direction of hoist, the other stated force for engaging the friction members of the friction clutch being adapted to be applied only to maintain the tautness of the element without shock to the object notwithstanding such motion of the element.

3. In a hoisting apparatus for hoisting a fragile object from a support subject to variable movement along the direction of hoist, the combination of power means, hoisting means including an element adapted to be connected to said object, means comprising a pair of separate members, one of said members being connected to said hoisting means and the other to said power means, said members having juxtaposed friction surfaces of varying projection, said surfaces having only portions of their areas in frictional engagement, means for forcing said surfaces into contact with sufficient frictional engagement only to maintain the element of the hoisting means free from objectionable slack upon the opera tion of said power means in the direction of hoist, while admitting of movement of said element in an opposite direction by the exertion of a part of the force'of-gravity of theobject upon' said element to compensate for movement of the support, and means for forcing said surfaces together with a sufiicient degree of frictional engagement to cause the operation of said power means to hoist the object. l

4. In a hoisting apparatus for hoisting a fragile object from a support subject to variable movement along the direction of hoist, the combination of power means, hoisting means including an element'adapted to be connected to said object. means comprising a pair of separate members, one of said members being connected to said hoist-- ing means and theother to said power means, said members having juxtaposedfrlction surfaces of varying projection, said surfaces having only portions of their areas in frictional engagement, fluid pressure meansfor forcing said surfaces into contact with sufficient frictional engagement only to maintain the element of the hoisting means free fro-m objectionable slack upon the operation of said power means in the direction of hoist, while admitting of movement of said element in an opposite direction by the exertion of a part of the force of gravity of the object upon said ele-' ment to compensate for movement of the sup port, and means for forcing said surfaces together with a sufficient degree of frictional engagement to-cause the operation of said power means to hoist the object. I

5. In a hoisting apparatus, the combination of hoisting means including an element adapted to be connected to the object to be hoisted, which object may be liable to impairment due to shock 4 incident to variable movement coincident with the direction of hoist, means including a pair of members having frictio-nally engageable surfaces for applying torque to the element in the direction of hoist; said surfaces being of different lateral projection with only a portion of the areas of said surfaces in frictional engagement, and fluid pressure means for frictionally engaging said members with a force whose torque upon the element is sufiicient only to hold the element taut against a minor portion of the gravity of the object and which torque will be overcome by a substantial portion of the gravity of the object, and at a different time with a force of greater magnitude whose torque will hoist the object.

6. In a hoisting apparatus, the combination of hoisting means including an element adapted to be connected to the object to be hoisted, which object may be liable to impairment due to shock incident to variable movement coincident with the direction of hoist, means including a pair of members having frictionally engageable surfaces for applying torque to the element in the direction of hoist; and fluid pressure means for frictionally engaging said members with a force whose torque upon the element is sufficient only to hold the element taut against a minor portion of the gravity of the object and which torque will be hoist, hoisting means including an element adapted to be connected to the object to be hoisted and driven by said power means only in the direction of hoist, which object may be liable to impairment due to shock incident to sudden motion,

of hoist, two members provided with juxtaposed surfaces of varying lateral projection with only a portion of the areas of said surfaces being adapted when in engagement to frictionally transmit driving torque; means for operatively connecting one of said members to the hoisting means and the other of said members to the power means; and means for producing relative movement between said members and for engaging the surfaces of said members with forces of dif-' ferent magnitudes for maintaining the element of the hoisting means free from objectionable slack preliminary to hoisting while admitting of movement of said element opposite to the direction of hoist by a minor portion of the force of the gravity of the object tocompensate for such movement of the support, and for hoisting the object, the torque of said power means being adapted, while said force of lesser magnitude engages said surfaces, to be overcome and the elesure means being provided with a fluid pressure chamber whose volume is variable by the variation in projection of the portions of the surfaces of said members in engagement.

9. The combination of claim '7 characterized by means for applying fluid under pressure to the engageable surfaces of the members to at times drivingly disconnect said surfaces.

10. The combination of claim '7 characterized by the means for producing relative movement between saidmembers being fluid pressure means adapted to apply fluid pressures of varying magnitude to one of said members, and means for applying fluid under pressure between said surfaces for lubrication and for breaking the frictional' engagement thereof.

11. In a hoisting apparatus, the combination of hoisting means adapted to be connected'to and hoist an object, said hoisting means being mounted adjacent water subjectable to wave action and said object being floatable on the Water adjacent said means and being liable to impairment by shock, power means, at-least one pair of members having juxtaposed engageable friction power transmitting surfaces having at least one space between said surfaces and adapted when said surfaces are in engagement to operatively connect the hoisting and the power means; means for applying lubricating fluid to said space; and means for engaging said surfaces for transmitting torque in the direction of hoist from the power to the hoisting means while the latter is connected to the object, said torque being insufiicient to overcome the gravity of the object, whereby the object may be maintained free from shock arising from and while connected to the hoisting means.

12. The combination of claim 11 further characterized by means for increasing such torque to a degree suflicient to hoist the object.

13. In a hoisting apparatus, the combination of hoisting means adapted to be connected to and hoist an object, said hoisting means being mounted adjacent Water subjectable to wave action and said object being floatable on the water adjacent said means and being liable to impairment by shock, power means, at least one pair of members having juxtaposed engageable friction power transmitting surfaces having only portions of such surfaces adapted to be in frictional engagement with spaces intermediate said engaged portions and adapted when said surfaces are in engagement to operatively connect the hoisting and the power means; and means for engaging said surfaces for transmitting torque in the direction of hoist from the power to the hoisting means While the latter is connected to the object, said torque being insufiicient to overcome the gravity of the object, means for increasing such torque to a degree sufficient to hoist the object, and means for maintaining a lubricating fluid in said spaces between said surfaces of said members.

14. The combination of claim 11 further characterized by at least one of said surfaces of the members being undulating with only portions of said surfaces being adapted to be in frictional engagement, and by means for relatively longitudinally movably mounting said members.

15. The combination of claim 11 further characterized by at least one of said surfaces of the members being undulating with only portions of said surfaces being adapted to be in frictional engagement, means for increasing said transmitted torque to a degree sufficient to hoist the object, and by said engaging means and increasing means being yieldable in the direction of said undulation.

16. The combination of claim 11 further characterized by at least one of said surfaces of the members being undulating with only portions of said surfaces being adapted to be in frictional engagement; means for relatively longitudinally movably mounting said members; means for increasing said transmitted torque to a degree sufiicient to hoist the object; and by hydraulic means, yieldable in the direction of said undulation, for operating said engaging and increasing means.

17. The combination of claim 11 further characterized by means for maintaining the disengagement of said surfaces of the members while said engaging means is not performing its engaging function.

18. The "combination of claim 11 further characterized by means for applying a lubricating fluid under pressure to and between said engageable surfaces for lubricating and maintaining the disengagement of said surfaces of the members while said engaging means is not performing its engaging function.

19. The combination of claim 11 further characterized by means for increasing said transmitted torque to a degree sufficient to hoist the object, and by means for maintaining the disengagement of said surfaces of the members with a force less than that exerted by said engaging means.

20. The combination of claim 11 further characterized by means for increasing said transmitted torque to a degree. sufiicient to hoist the object, by means for maintaining the disengagement of said surfaces of the members with a force less than that exerted by either the engaging means or the increasing means; and by hydraulic means for operating said engaging, increasing and maintaining means.

ALLAN J. CHANTRY. 

